Communication devices may transmit and receive communication data through a communication medium. In one example, the communication medium may be a wireless communication medium where communication data is transmitted and received by communication devices according to a wireless communication protocol. Example wireless communication protocols may include IEEE 802.11 protocols and BLUETOOTH® protocols in accordance with the Bluetooth Special Interest Group. In another example, the communication medium may be a wired communication medium where the communication data is transmitted and received according to a wire-based communication protocol. Some example wire-based protocols may include an Ethernet® protocol and/or a Powerline Communications protocol described by the HomePlug 2.0 specification. In yet another example, the communication medium may be a hybrid combination of wired and wireless communication mediums.
Analog signals within communication devices may undergo amplification during various processing operations. For example, an analog signal may be amplified during the process of receiving and/or transmitting a communication signal to and/or from another communication device. In some cases, as an analog signal is amplified, an unwanted frequency may also be amplified. For example, as a signal is amplified, an unwanted harmonic of the signal (e.g., a frequency spur) may also be amplified. The frequency spur may couple into a sensitive receive and/or transmit circuit and interfere with the transmission and/or reception of the communication signal.
Thus, there is a need to improve the processing of analog signals by suppressing unwanted frequencies, and thereby improve the performance of the communication device.